1. Field of the Invention
The present invention relates to a coaxial-type electric connector that is used by coupling a cable-shaped signal transmission medium such as a thin-wire coaxial cable thereto.
2. Description of Related Art
Generally, as signal transmission media which are used in various electronic devices or electric devices such as mobile phones or smartphones, cable-shaped signal transmission media such as thin-wire coaxial cables are widely employed, and a coaxial-type electric connector for efficiently connecting such a cable-shaped signal transmission medium to a printed wiring substrate is known. For example, in a coaxial-type electric connector described in Japanese Patent Application Laid-Open No. 2011-40262, an external conductor shell (shield shell) consisting of an approximately hollow cylindrical member is mounted in an outer peripheral side of an insulative housing, and a shell cover portion is openably/closably coupled to an annular opening of the external conductor shell. The shell cover portion which has been in an open state when a terminal portion of a cable-shaped signal transmission medium is coupled is configured to be closed so as to be pushed down together with an internal conductor contact disposed in an inner region of the external conductor shell. As a result, the internal conductor contact is plastically deformed so as to be bent, the cable-shaped signal transmission medium therefore becomes a sandwiched state, and electrical connection is established.
According to a coaxial electric connector having such a configuration, since the solder connection operation for coupling a cable-shaped signal transmission medium such as a coaxial cable to an internal conductor contact is omitted, assembly workability is improved, problems in environmental viewpoints such as disposal of a solder material are solved, and, in addition, an advantage that differences in characteristic impedance caused by differences of used amounts of solder are eliminated is also obtained.
However, in conventional coaxial-type electric connectors, there is a tendency that the matching degree (VSWR) of the characteristic impedance with respect to transmission signals becomes a mismatched state particularly along with recent advancement in high-frequency increase of transmission signals and rapid downsizing or height reduction of the electric connectors, and it is becoming difficult to maintain good high-frequency characteristics.
Hereby, the inventors of the present patent application disclose below prior literature, Japanese Patent Application Laid-Open No. 2011-40262.